From the past, projector devices of various types which project an image pattern formed upon a liquid crystal (LCD) panel or the like via a projection lens onto a screen have been known. And, from the past, such projectors have been large in size and high in price, and have mainly been used for business applications. However, in recent years the demand for large screen appreciation in typical households has increased, and, along with this, the shapes of such projector devices have also recently become quite compact, and their prices have also decreased to a level at which they can be purchased by individuals. In the past, a high luminance xenon lamp has been used as a light source. However, not only is such a lamp high in price, but moreover, along with a fixed procedure being required for turning it ON and OFF, also a fan has been required for dissipation of heat.
By contrast, light emitting diodes (LEDs) which generate low heat and are high in luminance have recently been developed. Moreover, as well as red colored LEDs and green colored LEDs, by also implementing LEDs which emit blue color as well, the development of projectors for consumer use which employ LEDs as light sources has progressed rapidly. In Japanese Laid-Open Patent Publication No. H8-234154 there is disclosed a reflective type SLM integrated photoelectric package in which one or more LEDs are used as a light source. And, in Japanese Laid-Open Patent Publication No. 2004-126144, there is disclosed an illumination unit which can provide extremely bright illumination by instantaneously emitting powerful light for a predetermined time period from each of several light emitting elements such as LEDs or the like.
On the other hand, in recent years, the diffusion of portable telephones has been spectacular, and, apart from normal conversation, they have been provided with various types of function such as email, internet, and the like. Moreover, recently the multi-functional capability of portable telephones has also progressed more and more, with portable telephones endowed with the function of photography and incorporating an image sensor having more than two megapixels being brought on the market.
Various types of invention have also been made in the past by combining a projector of the type described above and a portable device. In Japanese Laid-Open Patent Publication No. H3-65879 there is disclosed a camera with integrated projection display function, which employs a lens system of a photographic means also as a projection display means by using a half mirror or by using a total reflection mirror which rotates. In Japanese Laid-Open Patent Publication No. H5-137039 there is disclosed an electronic camera which is endowed with the function of a projector. With this electronic camera, an image may be projected upon a screen via the photographic lens by selectively fitting an eyepiece portion and a light. In Japanese Laid-Open Patent Publication No. H7-58814 there is disclosed a portable telephone device which is provided with an image projection unit in a predetermined position in the telephone device main body. And in Japanese Laid-Open Patent Publication No. 2001-21992 there is disclosed a portable telephone in which a display, a projector, and a control unit are housed within its chassis. In this publication, a light source unit consists of, for example, a white colored light emitting organic EL. Moreover in Japanese Laid-Open Patent Publication No. 2002-171428 there is disclosed a digital camera in which a CCD or optical system is shifted corresponding to the selection of projection mode.
And in Japanese Laid-Open Patent Publication No. 2002-199060 (US 2002-63855A) there is disclosed a portable type computing device including a circuit which transmits to a video projector output which is being displayed upon a display screen integral with the computing device. And in Japanese Translation of PCT International Application No. 2002-516044 (WO 98/19435) there is disclosed a portable communication device which includes a micro display system employing a compact high resolution active matrix liquid crystal display with an illumination system, and a magnification optical system. In this publication, an embodiment is disclosed in which a light source for backlighting employing a plurality of LEDs and a rear projection screen are used, so that several persons at one time are able to observe the image which is being displayed. Finally, in U.S. Pat. No. 6,489,934 there is disclosed a portable wireless device equipped with a projector which, as well as performing display of the entirety of an original page which has been received upon an incorporated display, also projects it upon an external screen.